James Staddon and William Pearson as the old and young Leo in The Go-Between: 'packs a singular emotional punch'. Photograph: Robert Day

The jewel-like precision of David Wood's adaptation is immediately apparent: LP Hartley's oft-quoted opening line to his 1953 novel is subtly but significantly altered. "The past is a foreign country; they do things differently there" becomes: "The past is a foreign country; you do things differently there!" This shift is instantly dramatic: the ageing narrator in dull, sensible tweeds angrily addresses the elegant Victorian ghosts conjured from the pages of his childhood diary. They, in turn, accuse the narrator of trapping them in the vice of his memory and demand release (for him as much as for themselves). The struggle to reconcile past and present springs theatrically to musical life.

Michael Pavelka's design hauntingly evokes the 1900 country house setting: a drawing room whose walls seem made from the faded silver backing of ancient mirrors, whose skew-angled doors open on to the promise of golden cornfields and wide, river-running spaces. Here, the worn, seam-cheeked narrator (a harrowed James Staddon) shadows the beautiful "angel" boy he once was (a shining William Pearson), simultaneously witnessing and reliving the child's transition from innocence to desolation via the experience of carrying letters between illicit lovers.

The increasingly menacing atmosphere and intricate emotional inter-relations are tellingly conveyed by Richard Taylor's score for solo piano (played on stage by musical director Jonathan Gill), voices and occasional bells. Impressionistic in its time-folding arpeggios and trills, rich in its mood-enhancing chords and otherworldly chimes, this music speakingly incorporates silence into its texture, which is as shimmering and delicate as Tim Lutkin's faded-sunshine lighting. Lyrics (by Wood and Taylor) are lucidly delivered by a vocally and physically impressive cast who, under Roger Haines's precise, choreographic direction, conjure vivid scenes – a fall from a haystack, a village cricket match – through fluid, unshowy movement. This multifaceted gem packs a singular emotional punch.